Process of manufacturing retarders for plaster



UNITED STATES PATENT OFFICE.

JAMES R. MCILVRIED, OF KANSAS CITY, MISSOURI, ASSIGNOR TO THE AMERICANSILIOAN COMPANY, OF OMAHA, NEBRASKA.

PROCESS OF MANUFACTURING RETARDERS FOR PLASTER.

SPECIFICATION forming part of Letters Patent No. 511,740, dated December26, 1893.

Application filed October 4, 1892. Serial No. 447,818- (No specimens.)

T at whom it may concern:

Be it known that I, JAMES R. MCILVRIED, of Kansas City, in the county ofJackson and State of Missouri, have invented a certain new and usefulProcess of Manufacturing Retarders for Plaster, of which the followingis a full, clear, and exact description.

My invention relates to a process of combining certain ingredients inthe manufacture of a setting-retarder for wall plaster; and my inventionconsists in certain features of novelty hereinafter described andpointed out in the claim.

It is well known in manufacturing plaster that when the same has beenprepared to the proper consistency for using, it shortly begins tosolidify or harden, and becomes unfit for use. I prepare a mixturewhich, when applied to the plaster proper retards the solidification toa greater or less degree, according to the amount of the mixture used,so the plaster can be prepared beforehand to be used at any length oftime required after the same has been prepared. I

The steps taken and proportions used in my process are substantially asfollows: One hundred pounds of lime is first air-slaked and kept in anair-tight receptacle for at least six months in order to add strength tothe lime. Then I mix water with the lime, bringing the same to theconsistency of cream, to which mixture I add fifty pounds of flour,fifty pounds of liquid glue and five pounds of wood ashes, bringing themixture to the consistency of thick paste; after which, I place the sameover a slow fire, stirring and. mixing it thoroughly until the compoundhas become dry, after which, I pulverize the same to a fine powder.

The above mentioned compound or composition of material is to be usedwith plaster of paris and sand to make a wall plaster, the proportionsbeing ten per cent. of the above mixture to every one hundred pounds ofplaster of paris and sand, or changed according to circumstances,depending on the time it is desired to use the plaster after the samehas been prepared. I can thus prepare my plaster to preventsolidification or hardening of the same and keep it in a plasticcondition until it is desired touse the same. If considerable time is toelapse between the mixing and the using, then a greater amount than tenper cent. of the mixture described should be added to the plaster; butif intended to be used at once, ten per cent. of the mixture will holdthe plaster in proper condition until it has been used.

I claim as my invention- The process of manufacturing a retardingmixture, consisting of air-slaking lime, keeping the same in anair-tight receptacle for a considerable period, then mixing the samewith water, dour, liquid glue and wood ashes to the consistency of thickpaste, and then drying the same over a slow fire and thoroughly mixingthe same until it becomes dry; substantially as herein described.

JAMES R. MOILVRIED.

Witnesses:

JAMES E. KNIGHT, i F. E. MULLETT.

